MPs have privately said they want a pay rise, with the majority calling for a 32% increase that would take their annual salary to £86,250.

The survey carried out by the Independent Parliamentary Standards Authority (Ipsa) also found more than a third believe they should keep generous final-salary pensions.

The findings emerged when Ipsa published a report on its initial consultation on pay and pensions, which ended last month.

The survey, which politicians completed anonymously, found that 69% thought they were underpaid on £65,738. The average level suggested for the salary was £86,250.

Tories said their salary should be £96,740, while Lib Dems thought the right amount was £78,361 and Labour £77,322. Other parties put the figure at £75,091 with a fifth of those questioned saying they should be paid £95,000 or more.

Ipsa, a watchdog created in the aftermath of the expenses scandal, declared that MPs pay would fall in line with the 1% public sector cap, announcing that their pay would rise to £66,396 in April and £67,060 the following year.

Ipsa rejected proposals to introduce performance-related pay, regional pay or to take outside earnings into account but signalled a potential rethink on resettlement grants for those who step down voluntarily.

It also disclosed that the prominent Tory backbench 1922 Committee and Parliamentary Labour Party had voiced "strong opposition" to fixing salaries as a multiple of national average earnings.

Critics described the findings as unpalatable and showing contempt for the public.

Matthew Sinclair, chief executive of the TaxPayers' Alliance said: "Hiking politician's wages at a time of pay freezes, benefit caps and necessary spending cuts would be completely unpalatable to taxpayers.

"To do so would suggest that there is one rule for MPs and another for the rest of the country."

Unison general secretary Dave Prentis said: "At a time when millions of workers are getting zero pay rises, the idea that MPs believe they deserve a 32% increase is living in cloud cuckoo land.

"MPs should get real about pay, Across the country public sector workers...are struggling because they have had their pay frozen for years. It would be good to hear them backing calls for a decent rise for these workers - instead of thinking about themselves.

"No wonder this research is anonymous, it shows real contempt for the plight of families across the country struggling to make ends meet."

In an anonymous comments section of the survey one MP wrote that such low levels of pay would soon mean that only MP's with private means would be able to enter parliament.

Another wrote: "Media commentators should shadow a week in the life of an average MP to understand the pressure, breadth of knowledge and social skills that are required to do the job. They have no idea."

The Ipsa proposals on pay and pensions would not be expected to come into force until after the next general election in 2015.

David Cameron shied away from proffering opinion. The Prime Minister's official spokesman said: "The Prime Minister's view is that MPs' pay is a matter for Ipsa. The 'I' in Ipsa stands for 'independent'."

The watchdog will put firm proposals out for consultation in the spring, with final decisions likely to be taken in the autumn.

Ipsa chairman Sir Ian Kennedy said: "In the past, MPs have agreed their pay and pensions among themselves. So this new approach of independent decision-making marks a real and important change and is another crucial step in helping Parliament to regain the trust of the public.

"We remain committed to listening and I would urge people to get involved in this debate."

• This article was amended on 11 January 2012 to remove the following sentence: "Conservatives were the most likely to believe they were underpaid, with 47% saying that was the case. Some 39% of Labour members and 9% of Lib Dems held the same view." These figures were incorrect; they were based on a misreading of the survey's breakdown of the weighted sample of 100 MPs polled into the number from each party who said they were underpaid: 39 out of 47 Conservative MPs (83%), 24 out of 39 Labour MPs (62%), five out of nine Liberal Democrat MPs (56%) and one out five "other" MPs (20%).